A person with whom one shares a rental property.

AKA a room mate or roomie.

Someone to split the rent with. (If they have the money)
Tom: Whoa, Somebody broke in and trashed your apartment while you were gone!
You: I wish. No, it was just my Flat mate, he's a pig.

You: Hey will you wash the dishes?
Flat mate: Ignores you and goes to his room.
by Pyro ND June 5, 2009
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(Noun) Friends that aren't so well endowed/have small breasts, relatively female.
by Syde Trak August 12, 2011
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